Early Triassic magnetic polarity time scale-integration of magnetostratigraphy, ammonite zonation and sequence stratigraphy from stratotype sections (Canadian Arctic Archipelago)

Details Early Triassic magnetic polarity time scale-integration of magnetostratigraphy, ammonite zonation and sequence stratigraphy from stratotype sections (Canadian Arctic Archipelago) Early Triassic magnetic polarity time scale-integration of magnetostratigraphy, ammonite zonation and sequence stratigraphy from stratotype sections (Canadian Arctic Archipelago)

Oct 1991

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1991e%26psl.107...69o&link_type=abstract

Earth and Planetary Science Letters, Volume 107, Issue 1, p. 69-89.

Physics

32

Scientific paper

Stratotypes defining the stages of the Early Triassic (Griesbachian, Dienerian, Smithian and Spathian) are located on Ellesmere and Axel Heiberg islands in the northern Canadian Arctic. Ammonite-rich horizons are within a clastic outer shelf-to-slope facies of thick progradational wedges of mudstones and siltstones. Three sections were sampled for magnetostratigraphy and interpreted for transgressive and regressive pulses of sedimentation. Using the ammonite zonation as a guide, the transgressive-regressive cycles and magnetostratigraphies have been correlated among the sections and to the published Triassic sequence stratigraphy time scale, thus enabling definition of the magnetic polarity pattern for the upper Griesbachian to Smithian stages in multiple sections. The magnetic polarity and associated sequence stratigraphy pattern for the lower Griesbachian and for the Spathian were derived from single sections. The Griesbachian and Dienerian stages each have two pairs of normal- and reversed-polarity chrons; the Smithian is predominantly of normal polarity, and the Spathian is predominantly of reversed polarity. This magnetic polarity time scale may help to resolve age correlations of North American redbed facies and to define the Permian-Triassic boundary.
After correction for variable structural orientations, the mean directions of magnetization from the three sites converge at 296° declination, 57° inclination (k = 60, α95 = 16.5° equivalent pole = 41°N, 161°E paleolatitude = 38°N), which is consistent with the pole derived from nearby Early Permian volcanics and supports a postulated post-Early Triassic, pre-Tertiary counterclockwise rotation of this region with respect to cratonic North America.

Affiliated with

Also associated with

No associations

Rating

Early Triassic magnetic polarity time scale-integration of magnetostratigraphy, ammonite zonation and sequence stratigraphy from stratotype sections (Canadian Arctic Archipelago) does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Early Triassic magnetic polarity time scale-integration of magnetostratigraphy, ammonite zonation and sequence stratigraphy from stratotype sections (Canadian Arctic Archipelago), we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Early Triassic magnetic polarity time scale-integration of magnetostratigraphy, ammonite zonation and sequence stratigraphy from stratotype sections (Canadian Arctic Archipelago) will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1875768